Breathable laminate permanently conformable to the contours of a wearer

ABSTRACT

A breathable, substantially liquid impermeable laminate is provided that is permanently conformable to the contours of a wearer&#39;s body when used in a personal care absorbent article or a medical article. The laminate includes a breathable (preferably microporous) film and a fibrous nonwoven web. Both the film and the web are extendible in a cross direction to a width at least 25% greater than an original, unstretched width upon application of a stretching force. The web and the film, and the overall laminate, exhibit little or no retractive force once they have been stretched. A diaper or other garment can be constructed in undersized fashion using the laminate, permitting material savings. When the garment is worn, the laminate stretches only where needed to provide a substantially perfect fit on the wearer. The minimal retractive force avoids the skin marks, rashes, etc. that can result from elastic garments.

FIELD OF THE INVENTION

This invention relates to a breathable laminate (i.e., breathable towater vapor but substantially liquid-impermeable) which is permanentlyconformable to the contour of a wearer. The laminate stretches as neededto conform to the contour of the wearer and remains, essentially, in itsextended or stretched state, even after a stretching force is removed.

BACKGROUND OF THE INVENTION

Laminates which are breathable to water vapor but substantiallyimpermeable to liquid water are known in the art, and are commonly usedin diaper backings, other personal care absorbent garments, medicalgarments and the like. These laminates may be composed of a breathable,stretch-thinned filled film and a spunbond web. The breathable film canbe formed by blending one or more polyolefins with an inorganicparticulate filler, forming a film from the mixture, and stretching thefilm to cause void formation around the filler particles. The resultingfilm may have thin polymer membranes around the filler particles whichpermit molecular diffusion of water vapor, while the overall filmsubstantially blocks transmission of liquid water, or may havemicropores going through the film. The breathable film can be laminatedto a nonwoven web, for instance, a spunbond web, by thermal or adhesivebonding. The spunbond web adds strength and integrity to the breathablelaminate, and provides a soft, cloth-like feel.

One trend affecting the personal care absorbent garment industry, andthe medical garment industry, involves the demand and need for productswith higher breathability to water vapor, which retain or increase thebarrier to water, blood and other liquid substances. This trend reflectsthe demand for increased wearer comfort without loss of barrierperformance. Another trend affecting these industries involves thedemand and need for products having better fit, which conform to thecontours of the wearer's body. To date, much of the investigation inthis area has involved use of elastic materials.

One challenge involving the use of elastic materials is that many of theproducts, including absorbent garments, have a complex layer structure.Absorbent garments typically include at least a liquid-permeable toplayer, an absorbent core layer, and a breathable, substantiallyliquid-impermeable outer cover laminate. If one of these materials ismade elastic, the absorbent garment will not necessarily be elastic. Inorder for the absorbent garment to have elastic properties, each layermust either a) exhibit a desired minimum level of stretching andretraction or b) be “free floating” and not attached to the elastic orextendible layers.

Another challenge of using elastic materials to promote conformabilityis the conversion of kinetic energy to potential energy duringstretching. The stored potential energy in the stretched regions of thegarment creates a retractive force which acts against the wearer's body,causing compression of the skin and discomfort.

Wherever an elastic garment is stretched in selected regions to conformto a wearer's body, the garment will exhibit a tighter fit in thestretched regions. Skin ripples, red marks or even rashes may form wherethe elastic material exhibits the greatest retractive force against thewearer's skin. These problems become more acute when the garmentcontains more than one elastic layer.

There is a need or desire in the industries of personal care absorbentgarments and medical garments, for less expensive materials whichstretch in order to conform to the contours of a wearer's body. There isalso a need or desire for materials which do not store significantamounts of potential energy when stretched, and which do not exhibitexcessive retractive force against the wearer's body. In short, there isa need or desire for materials and garments which remain stretched,i.e., which permanently conform to the contours of the wearer's body.

SUMMARY OF THE INVENTION

The present invention is directed to a substantially liquid-impermeablelaminate including at least one thermoplastic nonwoven filament web andat least one film, preferably a breathable, substantiallyliquid-impermeable film laminated to it. The laminate (which ispreferably breathable) has a machine direction (direction of formation)which corresponds to a primary direction of orientation of the nonwovenfilaments, and a cross direction which is perpendicular to the machinedirection. The breathable laminate is extendible in the cross directionto a stretched width that is at least 25% greater than an original,unstretched width upon application of a stretching force. When thestretching force is removed, the breathable laminate either does notretract, or retracts by not more than 30% of the difference between thestretched width and the original width.

The breathable, substantially liquid impermeable laminate preferablyincludes a breathable, microporous film having cross-directionalextendibility at least as great as the laminate, and a fibrous nonwovenweb, bonded to the film, which also has cross-directional extendibilityat least as great as the laminate. The film may alternatively be made ofan inherently breathable polymer. The component which has the leastcross-directional extendibility (whether the film or the web) will limitthe useful cross-directional extendibility of the entire laminate. Inother words, the laminate will extend to the same or a lesser extentthan the least extendible layer. Similarly, neither the film nor the webshould exhibit significantly more retractive force than is desired forthe laminate in general. If either the film or the web has a tendency toretract by more than 30% of the difference between its stretched widthand original unstretched width, then the overall laminate may retracttoo much or apply excessive retractive force against the wearer's body.

In one embodiment, the thermoplastic nonwoven filament web is aneck-stretched nonwoven web, for example, a neck-stretched spunbond web.The nonwoven web, which is made of a relatively inelastic polymermaterial, is extended in the machine direction to cause narrowing orneck-in of the web in the cross direction. The web is laminated andbonded to a breathable microporous film while the web is in the neckedcondition. The film includes at least one thermoplastic polymer whichrenders the film stretchable (but not elastic, or highly retractable) inthe cross direction. Thus, when the laminate is stretched in the crossdirection, the film is stretched, and the nonwoven web returns towardits original, un-necked state. The stretched laminate exhibits little orno retractive force after being held for one minute in the stretchedcondition. In this embodiment, the laminate has cross-directionalextendibility but may not have machine direction extendibility if thenonwoven web is made from a non-extendible polymer composition.

In another embodiment, the thermoplastic nonwoven web is not necessarilyneck-stretched, but is made using an extendible (but not elastic, orhighly retractable) polymer material. The film also includes at leastone thermoplastic polymer which renders the film extendible (but notelastic, or highly retractable) in the cross direction. When thelaminate is stretched in the cross direction, the film is stretched, andthe fibers in the nonwoven web are also stretched. The stretchedlaminate exhibits little or no retractive force. In this embodiment, thelaminate may have extendibility in the machine direction as well as thecross direction, since both the film and web are made from extendiblepolymers.

In another embodiment, the thermoplastic web is not necessarilyneck-stretched or made using a stretchable polymer. Instead, thenonwoven web is rendered stretchable by crimping of the filaments.Crimped filaments have undulations and/or spirals along their lengthwhich tend to straighten out when a stretching force is applied, thusrendering the filaments elongatable. Again, the film includes at leastone thermoplastic polymer which renders the film stretchable (but notelastic, or highly retractable) in the cross direction. When thelaminate is stretched in the cross direction, the film is stretched, andthe crimped filaments of the nonwoven web tend to straighten out. Again,the stretched laminate exhibits little or no retractive force. In thisembodiment, the laminate may have extendibility in the machine directionas well as the cross direction, since the film is made from anextendible polymer and the web will extend in either direction.

With the foregoing in mind, it is a feature and advantage of theinvention to provide a substantially liquid-impermeable (preferablybreathable) laminate which stretches where needed, and exhibits littleretractive force, thereby conforming permanently to the contour of awearer's body.

It is also a feature and advantage of the invention to provide alaminate which conforms to the contours of a wearer's body, and which isrelatively inexpensive to manufacture compared to prior art elasticlaminates.

It is also a feature and advantage of the invention to provide variouspersonal care and medical garments which incorporate the breathablelaminate of the invention, and which (due to their extendibility and lowretractions) permanently conform to the contour of a wearer's body.

The foregoing and other features and advantages will become furtherapparent from the following detailed description of the presentlypreferred embodiments, read in conjunction with the accompanyingdrawings. The detailed description and drawings are intended to beillustrative rather than limiting, the scope of the invention beingdefined by the appended claims and equivalents thereof

DEFINITIONS

The term “extendible” is used herein to mean a material which uponapplication of a stretching force, can be extended in a particulardirection, to a stretched dimension (e.g., width) which is at least 25%greater than an original, unstretched dimension. When the stretchingforce is removed after a one-minute holding period, the material doesnot retract, or retracts by not more than 30% of the difference betweenthe stretched dimension and the original dimension. Thus, a materialhaving a width of one meter, which is extendible in the cross direction,can be stretched to a width of at least 1.25 meters. When the stretchingforce is released, after holding the extended width for one minute, amaterial stretched to a width of 1.25 meters will not retract, or willretract to a width of not less than 1.175 meters. Extendible materialsare different from elastic materials, the latter tending to retract mostof the way to their original dimension when a stretching force isreleased. The stretching force can be any force sufficient to extend thematerial to between 125% of its original dimension, and its maximumstretched dimension in the selected direction (e.g., the crossdirection) without rupturing it.

The “percent retraction” is determined when the retractive force dropsbelow 10 grams for a 3-inch wide sample, using the procedure set forthin the Examples. “Percent permanent set” is 100 minus “percentretraction.” The term “inelastic” refers both to materials that do notstretch by 25% or more and to materials that stretch by that amount butdo not retract by more than 30%. Inelastic materials include extendiblematerials, as defined above, as well as materials that do not extend,e.g., which tear when subjected to a stretching force.

The term “machine direction” as applied to a nonwoven web, refers to thedirection of travel of a conveyor passing beneath the spinnerette orsimilar extrusion or forming apparatus for the filaments, which causesthe filaments to have primary orientation in the same direction. Whilethe filaments may appear wavy, or even randomly oriented in a localizedsection of a nonwoven web, they usually have an overall machinedirection of orientation which was parallel to the movement of theconveyor that carried them away from the extrusion or forming apparatus.

The term “machine direction” as applied to a film, refers to thedirection on the film that was parallel to the direction of travel ofthe film as it left the extrusion or forming apparatus. If the filmpassed between nip rollers or chill rollers, for instance, the machinedirection is the direction on the film that was parallel to the surfacemovement of the rollers when in contact with the film.

The term “machine direction” as applied to a laminate including at leastone film and at least one nonwoven web, refers to the machine directionof the nonwoven web component of the laminate.

The term “cross direction” for a nonwoven web, film, or laminate refersto the direction perpendicular to the machine direction. Dimensionsmeasured in the cross direction are referred to as “width” dimensions,while dimensions measured in the machine direction are referred to as“length” dimensions.

The terms “breathable film,” “breathable laminate” or “breathable outercover material” refer to a film, laminate, or outer cover materialhaving a water vapor transmission rate (“WVTR”) of at least about 300grams/m²—24 hours, using the WVTR Test Procedure described herein. Theterm “higher breathability” simply means that a second material has ahigher WVTR than a first material. Breathable materials typically relyon molecular diffusion of vapor, or vapor passage through micropores,and are substantially liquid impermeable.

The term “liquid water-permeable material” refers to a material presentin one or more layers, such as a nonwoven fabric, which is porous, andwhich is liquid water permeable due to the flow of water and otheraqueous liquids through the pores. The spaces between fibers orfilaments in a nonwoven web can be large enough and frequent enough topermit leakage and flow of liquid water through the material.

The term “nonwoven fabric or web” means a web having a structure ofindividual fibers or threads which are interlaid, but not in a regularor identifiable manner as in a knitted fabric. Nonwoven fabrics or webshave been formed from many processes such as, for example, meltblowingprocesses, spunbonding processes, air laying processes, coformingprocesses, and bonded carded web processes. The basis weight of nonwovenfabrics is usually expressed in ounces of material per square yard (osy)or grams per square meter (gsm) and the fiber diameters useful areusually expressed in microns. (Note that to convert from osy to gsm,multiply osy by 33.91.)

The term “microfibers” means small diameter fibers typically having anaverage fiber denier of about 0.005-10. Fiber denier is defined as gramsper 9000 meters of a fiber. For a fiber having circular cross-section,denier may be calculated as fiber diameter in microns squared,multiplied by the density in grams/cc, multiplied by 0.00707. For fibersmade of the same polymer, a lower denier indicates a finer fiber and ahigher denier indicates a thicker or heavier fiber. For example, thediameter of a polypropylene fiber given as 15 microns may be convertedto denier by squaring, multiplying the result by 0.89 g/cc andmultiplying by 0.00707. Thus, a 15 micron polypropylene fiber has adenier of about 1.42 calculated as (15 ²×0.89×0.00707=1.415). Outsidethe United States the unit of measurement is more commonly the “tex,”which is defined as the grams per kilometer of fiber. Tex may becalculated as denier/9.

The term “spunbonded fibers” refers to small diameter fibers which areformed by extruding molten thermoplastic material as filaments from aplurality of fine capillaries of a spinnerette having a circular orother configuration, with the diameter of the extruded filaments thenbeing rapidly reduced as by, for example, in U.S. Pat. No. 4,340,563 toAppel et al., and U.S. Pat. No. 3,692,618 to Dorschner et al., U.S. Pat.No. 3,802,817 to Matsuki et al., U.S. Pat. Nos. 3,338,992 and 3,341,394to Kinney, U.S. Pat. No. 3,502,763 to Hartmann, U.S. Pat. No. 3,502,538to Petersen, and U.S. Pat. No. 3,542,615 to Dobo et al., each of whichis incorporated herein in its entirety by reference. Spunbond fibers arequenched and generally not tacky when they are deposited onto acollecting surface. Spunbond fibers are generally continuous and oftenhave average deniers larger than about 0.3, more particularly, betweenabout 0.6 and 10.

The term “meltblown fibers” means fibers formed by extruding a moltenthermoplastic material through a plurality of fine, usually circular,die capillaries as molten threads or filaments into converging highvelocity heated gas (e.g., air) streams which attenuate the filaments ofmolten thermoplastic material to reduce their diameter, which may be tomicrofiber diameter. Thereafter, the meltblown fibers are carried by thehigh velocity gas stream and are deposited on a collecting surface toform a web of randomly dispersed meltblown fibers. Such a process isdisclosed for example, in U.S. Pat. No. 3,849,241 to Butin et al.Meltblown fibers are microfibers which may be continuous ordiscontinuous, are generally smaller than about 1.0 denier, and aregenerally self bonding when deposited onto a collecting surface.

The term “film” refers to a thermoplastic film made using a filmextrusion process, such as a cast film or blown film extrusion process.This term includes films rendered microporous by mixing polymer withfiller, forming a film from the mixture, and stretching the film.

The term “microporous” refers to films having voids separated by thinpolymer membranes and films having micropores passing through the films.The voids or micropores can be formed when a mixture of polymer andfiller is extruded into a film and the film is stretched, preferablyuniaxially in the machine direction. Microporous films tend to havewater vapor transmission due to molecular diffusion of water vaporthrough the membranes or micropores, but substantially block the passageof aqueous liquids.

The term “polymer” includes, but is not limited to, homopolymers,copolymers, such as for example, block, graft, random and alternatingcopolymers, terpolymers, etc. and blends and modifications thereof.Furthermore, unless otherwise specifically limited, the term “polymer”shall include all possible geometrical configurations of the material.These configurations include, but are not limited to isotactic,syndiotactic and atactic symmetries.

The term “absorbent article” includes personal care absorbent productsand medical absorbent products. The term “personal care absorbentproduct” includes without limitation diapers, training pants, swim wear,absorbent underpants, baby wipes, adult incontinence products, andfeminine hygiene products.

The term “medical absorbent product” includes without limitationabsorbent garments, underpads, bandages, face masks, absorbent drapes,and medical wipes.

The term “neck” or “neck stretch” interchangeably means that the fabric,nonwoven web or laminate is drawn such that it is extended underconditions reducing its width or its transverse dimension by stretchinglengthwise or increasing the length of the fabric. The controlleddrawing may take place under cool temperatures, room temperature orgreater temperatures and is limited to an increase in overall dimensionin the direction being drawn up to the elongation required to break thefabric, nonwoven web or laminate, which in most cases is about 1.2 to1.6 times. When relaxed, the fabric, nonwoven web or laminate does notreturn totally to its original dimensions. The necking process typicallyinvolves unwinding a sheet from a supply roll and passing it through abrake nip roll assembly driven at a given linear speed. A take-up rollor nip, operating at a linear speed higher than the brake nip roll,draws the fabric and generates the tension needed to elongate and neckthe fabric. U.S. Pat. No. 4,965,122 issued to Morman, and commonlyassigned to the assignee of the present invention, discloses areversibly necked nonwoven material which may be formed by necking thematerial, then heating the necked material, followed by cooling and isincorporated herein by reference in its entirety. The heating of thenecked material causes additional crystallization of the polymer givingit a partial heat set. If the necked material is a spunbond web, some ofthe fibers in the web may become crimped during the necking process, asexplained in U.S. Pat. No. 4,965,122.

The term “neckable material” or “neckable layer” means any material orlayer which can be necked such as a nonwoven, woven, or knittedmaterial, or a laminate containing one of them. As used herein, the term“necked material” refers to any material which has been drawn in atleast one dimension, (e.g., lengthwise), reducing the transversedimension, (e.g., width), such that when the drawing force is removed,the material can be pulled back to its original width. The neckedmaterial generally has a higher basis weight per unit area than theun-necked material. When the necked material is pulled back to itsoriginal width, it should have about the same basis weight as theun-necked material. This differs from stretching/orienting the filmlayer, during which the film is thinned and the basis weight is reduced.Preferred nonwoven webs for use in the invention are made from aninelastic polymer.

The term “percent neckdown” refers to the ratio determined by measuringthe difference between the un-necked dimension and the necked dimensionof the neckable material and then dividing that difference by theun-necked dimension of the neckable material.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a top view of a fibrous nonwoven web, which can be aspunbond web, which has not been necked.

FIG. 2 illustrates a top view of a fibrous nonwoven web, which can be aspunbond web, which has been necked.

FIG. 3 illustrates a sectional view of a breathable microporous filmwhich can be laminated to the nonwoven web of FIG. 1 or FIG. 2.

FIG. 4 schematically illustrates a process that can be used to form thebreathable laminates of the invention.

DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENTS

Referring to FIG. 1, a nonwoven web 10, which can be a spunbond web,includes a plurality of individual thermoplastic fiber elements 12intermittently bonded together using a bonding pattern which, in thisinstance, includes a plurality of point bonds 14. The individual fibers12 appear to have a wavy or somewhat random orientation when viewed on amicroscopic scale. When viewed on a microscopic scale, so that theentire lengths of fibers 12 are visible, the fibers 12 have an overallprimary direction of orientation which is parallel to a machinedirection, represented by arrow 16. If the nonwoven web is spunbond, itmay be intentionally produced with high machine-direction filamentorientation and thermal bonds oriented predominantly in the machinedirection. This will provide the spunbond web with inherentcross-directional extendibility, much like that existing in aconventional bonded carded web.

The nonwoven web 10 is preferably a spunbond web, but can also be ameltblown web, a bonded carded web, an air laid web, or a laminate orcomposite including one or more nonwoven webs. The nonwoven web may alsobe formed or modified using a hydraulic entangling process. In oneembodiment of the invention, the nonwoven web or laminate including it,is neckable, as defined above. FIG. 2 illustrates a top view of a neckednonwoven material 20, which can be the nonwoven web 10 stretched in themachine direction 16 to cause elongation of the web in the machinedirection 16 and narrowing, or neck-in, in the cross direction 18. Asshown in FIG. 2, necking causes the individual filaments 12 to becomemore aligned with each other, and closer to each other. When a neckablenonwoven web or laminate is employed, it should have a percent neck-downof at least about 15%, more preferably about 25-75%, most preferablyabout 35-65%. Prior to necking, the nonwoven web 10 should have a basisweight of about 0.05-4.0 ounces per square yard. (“osy”), preferablyabout 0.3-2.0 osy, more preferably about 0.4-1.0 osy.

When a neckable nonwoven web is used, the nonwoven web can beconstructed from either a non-extendible or an extendible polymer.Examples of suitable non-extendible polymers include, withoutlimitation, polyolefins, polyamides, and polyesters. Preferred polymersinclude polyolefins, such as polypropylene and/or polyethylene. Othersuitable polymers include copolymers of mainly ethylene and C₃-C₁₂alpha-olefins, having a density of about 0.900-0.935 grams 1cm³,commonly known as linear low density polyethylenes. Also included arecopolymers of at least 90% by weight propylene with not more than 10% byweight C₂ or C₄-C,₁₂ alpha-olefins. Extendible polymers (as describedbelow), which are preferred when the nonwoven web 10 is notneck-stretched or the fibers crimped, may also be used when it isneck-stretched. Single-site catalyzed polyolefins (i.e.,metallocene-catalyzed or constrained geometry-catalyzed) are alsouseful. These polyolefins may be extendible or not extendible, dependingon their density and monomer content. Single-site catalyzed polyolefinsare described in U.S. Pat. Nos. 5,571,619; 5,322,728; and 5,272,236, thedisclosures of which are incorporated by reference.

Polymers made using single-site catalysts have a very narrow molecularweight range. Polydispersity numbers (Mw/Mn) of below 4 and even below 2are possible for metallocene-produced polymers. These polymers also havea controlled short chain branching distribution compared to otherwisesimilar Ziegler-Natta produced type polymers. It is also possible usinga metallocene catalyst system to control the isotacticity of the polymerquite closely. In general, polyethylene polymers and copolymers having adensity of 0.900 grams/cc or greater tend to be less extendible or notextendible, while those having a density below 0.900 grams/cc are moreextendible. In general, polypropylene polymers and copolymers containing0-10% of an ethylene or other alpha-olefin comonomer tend to be lessextendible or not extendible, while propylene-alpha olefin copolymerscontaining more than 10% comonomer are more extendible.

Commercial production of single-site catalyzed polymers is somewhatlimited but growing. Such polymers are available from Exxon ChemicalCompany of Baytown, Tex. under the trade name ACHIEVE for polypropylenebased polymers and EXACT and EXCEED for polyethylene based polymers. DowChemical Company of Midland, Michigan has polymers commerciallyavailable under the name AFFINITY. These materials are believed to beproduced using non-stereo selective metallocene catalysts. Exxongenerally refers to their catalyst technology as single site ormetallocene catalysts while Dow refers to theirs as “constrainedgeometry” catalysts under the name INSITE to distinguish them fromtraditional Ziegler-Natta catalysts which have multiple reaction sites.Other manufacturers such as Fina Oil, BASF, Amoco, Hoechst and Mobil areactive in this area and it is believed that the availability of polymersproduced according to this technology will grow substantially in thenext decade.

In a second embodiment, the cross direction extendible nonwoven web 10is not neck-stretched. In this embodiment, the nonwoven web 10 is madefrom an extendible polymer material, i.e., one which permits theindividual fibers 12 to stretch by at least 25% of their initial length,and not retract by more than 30% of the difference between the stretchedlength and the unstretched length when a stretching force is removed.Preferably, the extendible polymer is one which permits the individualfibers 12 to stretch by at least 35% (e.g. 35-300%) of their initiallength, and not retract by more than 30% of the difference between thestretched and unstretched lengths when the stretching force is removed.More preferably, the extendible polymer permits the individual fibers 12to stretch by at least 50% (e.g. 50-200%) of their initial, unstretchedlength and not retract more than 30% of said difference. The extendiblefibers 12 may be composed of a blend or other combination of anextendible and non-extendible polymer, so long as the extendible polymeris present in sufficient quantity to render the fibers extendible.

Examples of extendible polymers include certain flexible polyolefins,for example propylene-based polymers having both atactic and isotacticpropylene groups in the main polypropylene chain. Flexible polyolefins(FPO's) are sold by the Rexene Corporation. Also included areheterophasic propylene-ethylene copolymers sold as “catalloys” by theHimont Corporation. Heterophasic polymers are reactor blends formed byadding different levels of propylene and ethylene at different stages inthe reactor. Heterophasic polymers typically include about 10-90% byweight of a first polymer segment A, about 10-90% by weight of a secondpolymer segment B, and 0-20% by weight of a third polymer segment C.Polymer segment A is at least about 80% crystalline and includes about90-100% by weight propylene, as a homopolymer or random copolymer withup to 10% by weight ethylene. Polymer segment B is less than about 50%crystalline, and includes about 30-70% by weight propylene randomlycopolymerized with about 30-70% by weight ethylene. Optional polymersegment C contains about 80-100% by weight ethylene and 0-20% ofrandomly copolymerized propylene.

Other extendible polymers include very low density polyethylene (VLDPE),which is an ethylene-alpha olefin copolymer having a density less than0.900 grams/cm³, preferably about 0.870-0.890 grams/cm³. PreferredVLDPE's are single-site catalyzed. Other extendible polymers includerandom propylene-alpha olefin copolymers containing more than 10% byweight of a C₂ or C₄-C ₂ comonomer, preferably about 15-85% by weight ofthe comonomer, with ethylene being a preferred comonomer.

In a third embodiment, the cross direction extendible nonwoven web 10 ismade of fibers 12 that are crimped. A wide variety of crimping processesare known in the art. Crimped fibers have accordion-like or spring-likeundulations or microundulations so that when the fibers are extended,they straighten out and/or the undulations are reduced in amplitude.When crimped fibers are used, the polymer of construction need not beextendible, i.e., may be extendible or not extendible.

In yet another embodiment, the nonwoven is formed so that the fibershave very high machine direction (MD) and very little cross direction(CD) orientation. The fibers are then bonded so as to minimize CDbonding of the fibers. This allows the material to extended in the CD.An example of such a material is a bonded carded web (BCW) nonwoven thathas high CD extendibility and low MD extendibility. Other nonwovens,such as spunbonds, can be made to perform like BCW's by forming thespunbond fibers so that the fibers are highly oriented in the MD andbond the filaments with a bond pattern so that the material can readilyextend in the CD. Such a bond pattern would have lower percent bond area(less than 25%) with the bonds lined up predominately in the MD. Thusthere are columns of fibers in the MD which are not bonded adjacent tocolumns of fibers in the MD that are. The unbonded fibers allow thenonwoven to readily extend in the CD while the bonded fibers give thematerial strength and abrasion resistance. BCW materials are describedfurther in Encyclopedia of Polymer Science and Engineering, Vol. 10,Pages 211-212, Wiley & Sons (1987), which is incorporated by reference.

FIG. 3, illustrates one embodiment of an extendible film, in this case abreathable extendible microporus film, that can be laminated to theneck-stretched nonwoven web of the first embodiment, the extendiblepolymer-based nonwoven web of the second embodiment, or the crimpednonwoven web of the third embodiment. The breathable microporous film100 can include a primary microporous core layer 112, sandwiched betweentwo thinner skin layers 122 and 124 which are used for bonding.Alternatively, the film 100 may include a primary microporous core layer112, and only one skin layer 122 or 124, or no skin layers.

The microporous layer 112 includes a polymer matrix 111, a plurality ofvoids 114 within the matrix surrounded by relatively thin microporousmembranes 113 defining tortuous paths, and one or more filler particles116 in each void 114. The layer 112 is microporous and breathable,wherein the microporous membranes 113 between the voids readily permitmolecular diffusion of water vapor from a first surface 118 to a secondsurface 120 of the film 100. Alternatively, some or all of themicropores can pass through the film, or can be interconnected toprovide through-passages.

The polymer matrix 111 can be formed from any extendible film-formingthermoplastic polymer. Examples of suitable polymers include withoutlimitation any one or more of the extendible polymers named above forthe second embodiment of the nonwoven web having extendible fibers. Theextendible polymer should be of a type and amount that causes the film100 to have cross-directional extendibility of at least about 25% of aninitial, unstretched width when a stretching force is applied. When thestretching force is relaxed, the film should not retract by more than30% of the difference between the stretched width and the initial,unstretched width. Preferably, film 100 should have cross-directionalextendibility of at least about 35% (e.g. 35-300%) of the initial width,more preferably at least about 50% (e.g. 50-200%). The extendiblepolymer may be blended with a non-extendible polymer so long as the filmhas the needed extendibility. Preferred polymers for the matrix 111 aresingle-site catalyzed ethylene copolymers and flexible polyolefins(FPOs) as described above.

The filler particles 116 can include any suitable inorganic or organicfiller. The filler particles 116 are preferably small to producemicropores, in order to maintain liquid water barrier of the film 100.Generally, the filler particles should have a mean particle diameter ofabout 0.1-7.0 microns, preferably about 0.5-5.0 microns, most preferablyabout 0.8-2.0 microns. Suitable fillers include without limitationcalcium carbonate, non-swellable clays, silica, alumina, barium sulfate,sodium carbonate, talc, magnesium sulfate, titanium dioxide, zeolites,aluminum sulfate, diatomaceous earth, magnesium sulfate, magnesiumcarbonate, barium carbonate, kaolin, mica, carbon, calcium oxide,magnesium oxide, aluminum hydroxide and polymer particles. Calciumcarbonate is a presently preferred filler.

The filler particles 116 may be coated with a minor quantity (e.g. up to2% by weight) of a fatty acid or other material to ease their dispersionin the polymer matrix. Suitable fatty acids include without limitationstearic acid, or a larger chain fatty acid such as behenic acid. Theamount of filler particles 116 in the core layer 112 of the film 100should range from about 10-55% by total (polymer and filler) volume ofthe layer 112, preferably about 15-45% by volume, most preferably about25-40% by volume. Similarly, the polymer matrix 111 should constituteabout 45-90% by volume of the core layer 112, preferably about 55-85% byvolume, more preferably about 60-75% by volume. The term “volume” refersto the total volume occupied by polymer and filler, and excludes airspace in the voids or micropores.

The polymer composition, filler content, filler particle size and degreeof stretching are factors which help determine the breathability andliquid barrier of the extendible microporous film 100 in the laminate.Generally, the oriented microporous film 100 will be less than about 50microns thick, preferably less than about 30 microns thick, mostpreferably less than about 20 microns thick. The film 100 may beuniaxially stretched to about 1.1-7.0 times its original length to causebreathability, preferably to about 1.5-6.0 times its original length,most preferably to about 2.5-5.0 times its original length. The film mayalternatively be biaxially stretched using conventional techniquesfamiliar to persons skilled in the art. Preferably, the film isuniaxially stretched in its machine direction, and is laminated to thenonwoven web with the machine direction of the film aligned with themachine direction of the web. Stretching temperatures may range fromabout 38-150° C. depending on the specific polymers employed, and arepreferably about 70-95° C. The breathable extendible film 100 can beprepared by cast or blown film coextrusion of the layers, by extrusioncoating, or by any conventional layering process.

In the embodiment of FIG. 3, the microporous breathable film layer 112is adjacent one or two relatively thin outer skin layers 122 and 124, ina two or three-layer extendible film 100. The inclusion of one or twoskin layers improves film processability and can also contribute heatseal properties to the breathable extendible film 100. The polymers inthe outer layers 122 and 124 can be the same or different than thepolymers in the microporous layer 112. Preferably, the polymers in theouter layer or layers are extendible, have a lower softening point thanin the microporous layer 112, and contribute to the heat sealability ofthe film 100. To facilitate breathability, the skin layers 122 and 124may contain a particulate filler in any quantity up to the same amountas the microporous core layer 112, and the skin layers may bemicroporous as well after the film is oriented.

Also, the thickness and composition of the outer layers 122 and 124should be selected so as not to substantially impair the moisturetransmission through the breathable film 100. This way, the microporouscore layer 112 may determine the breathability of the entire film. Tothis end, the skin layer 122 and 124 is generally less than about 10microns thick, preferably less than about 5 microns thick. The combinedskin layers should constitute no more than 25% of the entire filmthickness, and preferably constitute about 2-15% of the film thickness,more preferably 3-5% of the total film thickness. Preferred extendibleskin layer polymers having low softening points include amorphousmetallocene or Ziegler Natta-catalyzed copolymers of ethylene with aC₃-C₂₀ alpha-olefin comonomer, having a density less than about 0.89grams/cc. Also suitable are amorphous poly alpha-olefin (APAO) polymerswhich can be random copolymers or terpolymers of ethylene, propylene,and butene, and other substantially amorphous or semi-crystallinepropylene-ethylene polymers. Also included are ethylene vinyl acetates,propylene vinyl acetates, ethylene methyl acrylates, and blends of anyof the foregoing polymers.

The cross direction extendible microporous film 100 should have a watervapor transmission rate (“WVTR”) of at least 300 grams/m²—24 hours,measured using the procedure described below. Preferably, film 100should have a WVTR of at least 1200 grams/m²—24 hours, more preferablyat least 2000 grams/m²—24 hours.

FIG. 4 illustrates an integrated process for forming a multilayerbreathable film and a laminate. Referring to FIG. 4, film 100 is formedfrom a film coextrusion apparatus 40 such as a cast or blown unit whichcould be in-line or off-line. Typically the apparatus 40 will includetwo or three extruders 41. To make the core layer, filled resinincluding the polymer matrix material and filler is prepared in a mixer(not shown) and directed to an extruder 41. To make each skin layer,similar additional mixing apparatus (not shown) and extrusion apparatus41 can be used to mix the incompatible polymer components and extrudethem as skin layers on one or both sides of the core layers. Themultilayer film 100 is extruded onto a chill roller 42, which cools thefilm 100. A vacuum box 43 adjacent the chill roller creates a vacuum onthe surface of the chill roller to help maintain the film close to thesurface of the chill roller. Air knives or electrostatic pinners 44 alsourge the film 100 against the roller surface.

From the film extrusion apparatus 40 or off-line rolls supplied, themultilayer film 100 is directed to a film stretching unit 47 which canbe a machine direction orienter, commercially available from vendorsincluding the Marshall and Williams Co. of Providence, Rhode Island.Apparatus 47 has a plurality of stretching rollers 46 a-e, whichprogressively stretch and thin the film in the machine direction, whichis the direction of travel of the film. The rollers 46 a-e, which areheated to the desired stretching temperature, apply an amount of stressand progressively stretch the multilayer film 100 to a stretched lengthwhere the core layer 112 becomes microporous and breathable, and theskin layers 122 and 124 become sufficiently thin, and perhapsmicroporous, so as not to inhibit overall film breathability. While theapparatus 47 is shown with five stretching rollers 46 a-e, the number ofrollers may be greater or less depending on the level of stretch desiredand the amount of stretching between each pair of rollers.

Advantageously, the film 100 may be uniaxially stretched to about1.1-7.0 times its original length, preferably about 1.5-6 times itsoriginal length, suitably about 2.5-5 times its original length, usingan elevated stretch temperature as explained above. The elevated stretchtemperature can be sustained by heating some or all of the stretchrollers 46 a-e. The optimum stretch temperature varies with the corelayer and skin layer polymers of film 100, and is generally below themelting temperature of the matrix polymer in the core layer 112.

The multilayer film 100 may be laminated to one or more substrates, suchas a nonwoven web, using conventional adhesive bonding or thermalbonding techniques known in the art. The type of substrate and bondingwill vary depending on the particular end use application. Referringagain to FIG. 4, film 100 may be laminated to nonwoven web 20immediately after the film is stretched. In one embodiment, a neckablenonwoven web 20, which can be a spunbond web, is unwound from a supplyroll 62. The neckable material 20 then passes through the nip 64 ofS-roll arrangement 66, formed by a stack of rollers 68-70, in a reverseS-wrap path as shown by the arrows. Rollers 68 and 70 turn at a slowercircumferential speed than downstream calender bonding rollers 58,causing tensioning and neck-in of web 20. The tensioned, necked materialcan be passed under spray equipment 72 (e.g., a meltblown die) whichsprays adhesive 73 through die head 74 onto a surface of web 20. With orwithout the adhesive treatment, the necked web 20 can then be joined tomultilayer film 100 and bonded between calender rollers 58, which can beheated if necessary. The film 100 in FIG. 4 is simultaneously bonded onits other side to a second material 30 originating from supply roll 63.The second extendible material 30 may be a second nonwoven web, oranother film layer. The resulting laminate 32 is wound and stored on asupply roll 60. In addition to the described bonding technique, otherbonding techniques (e.g., other thermal, adhesive or ultrasonic bonding)may be employed.

The desired cross-directional extendibility of laminate 32 is preferablyachieved by aligning extendible breathable film 100 with the crossdirection extendible webs 20 and 30, so that both are traveling in theirrespective machine directions during bonding, and the machine directionsof the film and web are substantially parallel to each other. If thenonwoven web 20 is a necked web, the cross-directional extendibility ofthe laminate is achieved by returning the web toward its initial,un-necked state as the film and web are extended in the cross direction.If the nonwoven web is not necked but made of an extendible polymer,then its fibers are extended as the film is extended in the crossdirection. If the nonwoven web is made from crimped fibers, then itsfibers merely become less crimped or un-crimped as the film is extendedin the cross direction. The fibers can be both crimped and made from anextendible polymer, or present in a bonded carded web. Because thebreathable film has already been stretched in its machine directionprior to lamination, the film has a greater tendency to extend in thecross direction after lamination, than to extend further in the machinedirection.

The overall laminate 32 has cross-directional extendibility influencedby the extendabilities of the film and nonwoven web. Specifically, thelaminate has a cross-directional extendibility of at least 25% of itsinitial width, preferably at least 35% of its initial width, morepreferably at least 50% of its initial width when a stretching force isapplied, without rupturing the laminate. When the stretching force isremoved, the laminate does not recover or retract by more than 30% ofthe difference between the fully stretched width and the original widthafter a one-minute holding period.

Another way to characterize the laminate of the invention, is in termsof the percent drop in retractive force experienced during a one-minuteholding period in the stretched condition. The procedure for measuringthe percent drop in retractive force is set forth below in the Examples.Briefly, a sample of the laminate material is extended in the crossdirection by 50% of its initial width. The retractive force is measuredimmediately after extending the material by 50%, and after a one-minuteholding period in the extended condition. The percent force drop iscalculated as:${\% \quad {force}\quad {drop}} = {100 \times \left\lbrack \frac{\begin{matrix}{{{retractive}\quad {force}\quad \left( {{time} = 0} \right)} -} \\{{retractive}\quad {force}\quad \left( {{time} = {60\quad \sec}} \right)}\end{matrix}}{{retractive}\quad {force}\quad \left( {{time} = 0} \right)} \right\rbrack}$

To stay within the limited retraction required by the invention, thelaminate should exibit a percentage force drop of at least about 35%,preferably at least about 45%.

The cross direction extendible, breathable laminate may be used in awide variety of personal care absorbent articles and medical articles.Absorbent articles include without limitation diapers, training pants,swim wear, absorbent underpants, adult incontinence products, femininehygiene products, and the like. Medical products include medicalgarments, face masks, underpads, bandages, drapes, medical wipes, andthe like.

The cross direction extendible, breathable laminate has the advantage ofbeing selectively extended only in regions where stretching is needed,to conform to the contours of a wearer's body. For example, a diaper orpant-like absorbent garment embodying the laminate as an outercover canbe made smaller, using less material than a diaper that is notstretchable. When the absorbent garment is applied to a wearer, itstretches in the cross direction only where needed (for example, in thefront and back of the wearer) to ensure a perfect fit. Becauseretractive forces are minimal, the problem of skin marks and rashesoccurring in the regions of greatest stretch is substantially overcome.

WVTR TEST PROCEDURE

The following procedure is described for testing of the water vaportransmission rate (WVTR) for the films of the invention. The WVTR ismeasured in a manner similar to ASTM Standard Test Method for WaterVapor Transmission of Materials, Designation E-96-80 as follows. For thepurposes of the present invention, 3 inch diameter (76 mm) circularsamples are cut from the test material and from a control material,CELGARD® 2500 (Hoechst Celanese Corporation). CELGARD 2500 is a 0.0025cm thick film composed of microporous polypropylene. Two or threesamples are prepared for each material. Test cups used for testing arecast aluminum, flanged, 5.1 centimeters deep and come with a mechanicalseal and neoprene gasket. The cups are distributed by Thwing-AlbertInstrument Company, Philadelphia, Pa., under the designation Vapometercup no. 68-1. One hundred millimeters of distilled water are poured intoeach Vapometer cup, and each of the individual samples of the testmaterials and control material are placed across the top area of anindividual cup. Screw-on flanges are tightened to form a seal along theedges of the cups leaving the associated test material or controlmaterial exposed to the ambient atmosphere over a 62 millimeter diametercircular area (an open, exposed area of about 30 cm²). The cups are thenweighed, placed on a tray, and set in a forced air oven set at 100° F.(38° C.). The oven is a constant temperature oven with external airthrough it to prevent water vapor accumulation inside. A suitable forcedair oven is, for example, a Blue M Power-O-Matic 60 oven distributed byBlue M Electric Co. of Blue Island, Ill. After 24 hours, the cups areremoved from the oven and weighed. The preliminary, test WVTR value iscalculated as follows:

Test WVTR=[(grams weight loss over 24 hours)×7571]÷24

The relative humidity within the oven is not specifically controlled.Under predetermined set conditions of 38° C. and ambient relativehumidity, the WVTR for CELGARD 2500 has been defined as 5000 g/m²—24hours. Accordingly, CELGARD 2500 is run as a control sample with eachtest and the resulting values are corrected in accord with the variationof the control relative to its known WVTR.

EXAMPLES

Several laminates were prepared using a three-layer A-B-A cast film soldas Huntsman Type 1885, available from Huntsman Packaging Corp., 199Edison Drive, Washington, Ga. 30763. The film had a core layercontaining 42% by weight linear low density polyethylene and 58% byweight calcium carbonate filler. The film had two skin layers containinga mixture of ethylene vinyl acetate (28% vinyl acetate content), and aheterophasic combination of propylene-ethylene copolymers known asMontell KS-037P catalloy. The skin layers constituted about 3% of thetotal film thickness.

The film was stretched in the machine direction to 3.8-4.0 times itsoriginal length, yielding a breathable microporous film having a WVTR inexcess of 2000 grams/m²—24 hours. The breathable film had a basis weightof 19 grams/square meter.

In a first set of Examples (using low necked spunbond), the breathablefilm was adhesively laminated to a reversibly necked spunbond web using3 grams/square meter of Findley H2525A, an adhesive made by Ato Findleyof Milwaukee, Wisconsin, a division of Elf Autochem of France. Theadhesive was applied with a meltblown die tip. The reversibly neckedspunbond was prepared from a commercial polypropylene spunbond having abasis weight of 0.4 ounces/yd.², passed over 200° F. heated rolls, anddrawn by 6% using 100 ft/min unwind rolls and 106 ft/min re-wind rollswith a 16-foot free span between them. The drawing caused necking of thespunbond web from a 17-inch original width to an 11-inch necked width (aneck-in of 35%). The necked material was then passed over rolls heatedto 200° F., to make the reversibly necked spunbond web, as described inU.S. Pat. No. 4,965,122, issued to Morman, the disclosure of which isincorporated by reference.

In a second set of Examples (using high necked spunbond), the samemeltblown adhesive was used at the same level, to bond the breathablefilm and necked spunbond web. The highly necked spunbond was preparedfrom a commercial polypropylene spunbond having a basis weight of 0.5ounces per yd.², which was thermally point bonded at 305° F. Thespunbond web was necked prior to entering and in an oven set at 260° F.,from a 123-inch original width to a 44-inch necked width (a firstneck-in of 64%). The web was slit to a 17-inch width. A roll of the17-inch wide material was unwound and further necked to a 14-inch width(for a total neck-in of 70%) before being adhesively bonded to thebreathable microporous film.

In a third set of Examples (using a spunbond prepared from crimpedfibers), the same meltblown adhesive was used at the same level, to bindthe breathable film to the spunbond web. The spunbond web was thermallypoint bonded, and made from side-by-side bicomponent fibers. Thebicomponent fibers contained 70% by weight PP3155 polypropylene fromExxon Chemical Co. of Houston, Tex.; extruded adjacent to 30% by weightPEXflex® FPO (flexible polyolefin) WL201 from Huntsman Chemical Corp.,which is a propylene copolymer. The spunbond web had a basis weight of0.67 ounces/square yard and a cross-directional peak elongation of 200%.

The data set forth below, for each of the Examples, were generated usingthe following Procedure For One Cycle/Hold Tensile Test.

Procedure For One Cycle/Hold Tensile Test

A sample of laminate material is cut to 3″ long (MD) and 6″ wide (CD).An MTS Sintec Model 1/S (Serial#1S/062196/197) is used to evaluate thepermanent set properties of the material. The gauge length is 3″, andthe area of material being tested was 9 square inches (3″×3″). Thecrosshead speed is set to 1000 mm/min to simulate the extension thematerial would experience in diaper donning. The material is held atfull elongation for 60 seconds. The cycle elongation is set to thevarious elongations of interest. The elongation is set 3% lower than theactual target because it was found that the Sintec will slightlyovershoot the set elongation because of the high crosshead speed. Forexample, if a 50% elongation and hold is desired, the cycle elongationis set to 47%.

The material is clamped in the jaws. The material is stretched in thesample length (cross direction of the material) to the desiredelongation (25%, 50%, 100%, 150%, or 200%) and held in the elongatedstate for 60 seconds. The jaws are then returned to their original startposition.

For the following Examples, two hundred data points were collected andrecorded by the computer for each of the three step procedure: 1)elongation, 2) hold and 3) return to zero. The data analyzed was: 1) theforce on the sample for the last data point before the crosshead stoppedduring the elongation step 2) the force on the sample just before thecrosshead started to return to zero, 3) the actual elongation of thesample, and 4) the elongation of the sample when the force on the samplereturned to 10 grams or less during the “return to zero” step.

Examples 1 and 2 (First Set)

For Example 1, the laminate prepared using the low necked spunbondmaterial described above was extended in the cross direction by 25% ofits initial width, then held for 60 seconds, then permitted to retract.For Example 2, the low necked spunbond material was extended in thecross direction by 50% of its initial width, then held for 60 seconds,then permitted to retract. Three samples were run for each Example, andthe results were averaged. The following average results weredetermined.

TABLE 1 Force at Force Drop Exam- % Extended at Extended % ple Exten-Width, grams, Width, Permanent % No. sion no delay 1-min delay SetRetraction 1 25 530 52% 74% 26% 2 50 768 47% 82% 18%

As shown above, the laminate made using the breathable microporous filmand the low neck-stretched spunbond can be extended in the crossdirection by 25% or 50% of its original width without rupturing. Afterbeing held at the stretched width for one minute, the laminate retracts,in both cases, by less than 30% of the difference between the stretchedwidth and the original, unstretched width.

Examples 3-6 (Second Set)

For Example 3, the laminate prepared using the highly necked spunbondmaterial described above was extended in the cross direction by 50% ofits initial width, then held for 60 seconds, then permitted to retract.Similar procedures were followed for Examples 4-6, except that thematerial was extended in the cross direction by 100%, 150%, and 200%,respectively. Again, three samples were run for each Example, and theresults were averaged. The following average results were determined.

TABLE 2 Force at Force Drop Exam- % Extended at Extended % ple Exten-Width, grams, Width, Permanent % No. sion no delay 1-min delay SetRetraction 3 50 583 50% 74% 26% 4 100 650 51% 78% 22% 5 150 858 51% 80%20% 6 200 1205 48% 83% 17%

As shown above, the laminate made using the breathable microporous filmand the highly neck-stretched spunbond web can be extended in the crossdirection by 50%, 100%, 150% or 200% without rupturing. After being heldat the stretched width for one minute, the laminate retracts, in allcases, by less than 30% of the difference between the stretched widthand the original, unstretched width.

Examples 7-10 (Third Set)

For Example 7, the laminate prepared using the spunbond prepared fromcrimped fibers, as described above, was extended in the cross directionby 50% of its initial width, then held for 60 seconds, then permitted toretract. Similar procedures were followed for Examples 8-10, except thatthe laminate was extended in the cross direction by 100%, 150% and 200%,respectively. Again, three samples were run for each Example, and theresults were averaged. The following average results were determined.

TABLE 3 Force at Force Drop Exam- % Extended at Extended % ple Exten-Width, grams, Width, Permanent % No. sion no delay 1-min delay SetRetraction 7 50 505 49% 79% 21% 8 100 678 47% 81% 19% 9 150 850 47% 82%18% 10 200 1135 46% 82% 18%

As shown above, the laminate made using the breathable microporous filmand spunbond web prepared from an extendible polymer combination, can beextended in the cross direction by 50%, 100%, 150% or 200% withoutrupturing. After being held at the stretched width for one minute, thelaminate retracts, in all cases, by less than 30% of the differencebetween the stretched width and the original, unstretched width.

While the embodiments of the invention disclosed herein are presentlyconsidered preferred, various modifications and improvements can be madewithout departing from the spirit and scope of the invention. The scopeof the invention is indicated by the appended claims, and all changesthat fall within the meaning and range of equivalents are intended to beembraced therein.

We claim:
 1. A substantially liquid-impermeable laminate that isconformable to contours of a wearer's body, the laminate comprising: afilm that is extendible in a cross direction to a stretched width atleast 25% greater than an original, unstretched width upon applicationof a stretching force, and retractable by zero to not more than 30% of adifference between the stretched width and the original width uponrelaxation of the stretching force after 60 seconds; and laminated tothe film, a fibrous nonwoven web that is extendible in a cross directionto a stretched width at least 25% greater than an original, unstretchedwidth upon application of the stretching force, and retractable by notmore than 30% of a difference between the stretched width and theoriginal width upon relaxation of the stretching force.
 2. The laminateof claim 1, wherein the film and fibrous nonwoven web are extendible inthe cross direction to stretched widths at least 35% greater than theiroriginal, unstretched widths upon application of a stretching force. 3.The laminate of claim 1, wherein the film and fibrous nonwoven web areextendible in the cross direction to stretched widths at least 50%greater than their original, unstretched widths upon application of astretching force.
 4. The laminate of claim 1, wherein the nonwoven webis neck-stretched to cause elongation in a machine direction andnarrowing in its cross direction prior to being laminated to the film.5. The laminate of claim 4, wherein the nonwoven web comprises a polymerselected from polyamides, polyesters, linear low density polyethyleneshaving a density of 0.900-0.935 grams/cm³, propylene-alpha olefincopolymers containing at least 90% by weight propylene, and combinationsthereof.
 6. The laminate of claim 1, wherein the nonwoven web comprisesfibers made from an extendible polymer.
 7. The laminate of claim 6,wherein the nonwoven web comprises an extendible polymer selected fromextendible polyolefins, ethylene-alpha olefin copolymers having adensity less than 0.900 grams/cm³, propylene-alpha olefin copolymerscontaining more than 10% by weight of an alpha-olefin comonomer,heterophasic propylene-ethylene copolymers, propylene polymerscontaining both atactic and isotactic propylene groups, and combinationsthereof.
 8. The laminate of claim 1, wherein the nonwoven web comprisescrimped fibers.
 9. The laminate of claim 8, wherein the film comprises abreathable extendible polymer.
 10. The laminate of claim 8, wherein thefilm comprises a mixture of an inorganic particulate filler and anextendible polymer.
 11. The laminate of claim 1, wherein the filmcomprises a breathable film.
 12. The laminate of claim 1, wherein thenonwoven web comprises a spunbond web.
 13. The laminate of claim 1,wherein the nonwoven web comprises a meltblown web.
 14. The laminate ofclaim 1, wherein the nonwoven web comprises a bonded carded web.
 15. Thelaminate of claim 1, wherein the nonwoven web comprises an air laid web.16. The laminate of claim 1, wherein the nonwoven web comprises morethan one layer.
 17. The laminate of claim 1, wherein the film comprisesan extendible polymer selected from extendible polyolefins,ethylene-alpha olefin copolymers having a density less than 0.900grams/cm³, propylene-alpha olefin copolymers containing more than 10% byweight of an alpha-olefin comonomer, heterophasic propylene-ethylenecopolymers, propylene polymers containing both atactic and isotacticpropylene groups, and combinations thereof.
 18. A personal careabsorbent article comprising the laminate of claim
 1. 19. A medicalabsorbent article comprising the laminate of claim
 1. 20. A breathable,substantially liquid-impermeable laminate that is extendible in a crossdirection to a stretched width at least 25% greater than an original,unstretched width upon application of a stretching force, andretractable by zero to not more than 30% of a difference between thestretched width and the original width upon relaxation of the stretchingforce after 60 seconds, the laminate comprising: a breathablemicroporous film having cross-directional extendibility at least asgreat as the laminate; and a nonwoven web having cross-directionalextendibility at least as great as the laminate.
 21. The laminate ofclaim 20, wherein the breathable microporous film comprises a mixture ofan extendible thermoplastic polymer and an inorganic particulate filler,formed into a film and stretch-thinned in a machine direction.
 22. Thelaminate of claim 20, wherein the stretched width is about 25-75%greater than the original, unstretched width.
 23. The laminate of claim20, wherein the stretched width is about 35-65% greater than theoriginal, unstretched width.
 24. The laminate of claim 20, wherein thenonwoven web comprises a neck-stretched material.
 25. The laminate ofclaim 20, wherein the nonwoven web comprises an extendible polymermaterial.
 26. The laminate of claim 20, wherein the nonwoven webcomprises crimped fibers.
 27. A personal care absorbent articlecomprising the laminate of claim
 20. 28. A medical garment comprisingthe laminate of claim
 20. 29. A breathable, substantially liquidimpermeable laminate having a WVTR of at least 300 grams/m²—24 hours,comprising: a breathable microporous film extendible in a crossdirection to a stretched width at least 25% greater than an original,unstretched width upon application of a stretching force; and athermoplastic fibrous nonwoven web extendible in a cross direction to astretched width at least 25% greater than an original, unstretched widthupon application of the stretching force; wherein the film and nonwovenweb are aligned with a machine direction of the film substantiallyparallel to a machine direction of the web; and the laminate retracts by0-30% of a difference between a stretched width and an original,unstretched width when the stretching force is removed after 60 seconds.30. The laminate of claim 29, wherein the WVTR is at least 1200grams/m²—24 hours.
 31. The laminate of claim 29, wherein the WVTR is atleast 2000 grams/m²—24 hours.
 32. The laminate of claim 29, wherein thefilm and web are thermally bonded together.
 33. The laminate of claim29, wherein the film and web are adhesively bonded together.
 34. Thelaminate of claim 29, wherein the film and web are ultrasonically bondedtogether.
 35. A diaper comprising the laminate of claim
 29. 36. Trainingpants comprising the laminate of claim
 29. 37. Swim wear comprising thelaminate of claim
 29. 38. Absorbent underpants comprising the laminateof claim
 29. 39. An adult incontinence product comprising the laminateof claim
 29. 40. A feminine hygiene product comprising the laminate ofclaim
 29. 41. A medical product comprising the laminate of claim
 29. 42.A breathable, substantially liquid impermeable laminate having a WVTR ofat least 300 grams/m²—24 hours, comprising: a breathable microporousfilm extendible in a cross direction to a stretched width at least 50%greater than an original, unstretched width upon application of astretching force; and a thermoplastic fibrous nonwoven web extendible ina cross direction to a stretched width at least 50% greater than anoriginal, unstretched width upon application of the stretching force;wherein the film and nonwoven web are aligned with a machine directionof the film substantially parallel to a machine direction of the web;and the laminate exhibits a drop in retractive force of at least about35% after being extended to a stretched width 50% greater than theunstretched width, and maintained at the stretched width for 60 seconds.43. The laminate of claim 42, wherein the drop in retractive force is atleast about 45%.
 44. The laminate of claim 42, wherein the WVTR is atleast 2000 grams/m²—24 hours.
 45. The laminate of claim 42, wherein thefilm and web are thermally bonded together.
 46. The laminate of claim42, wherein the film and web are adhesively bonded together.
 47. Thelaminate of claim 42, wherein the film and web are ultrasonically bondedtogether.
 48. A diaper comprising the laminate of claim
 42. 49. Trainingpants comprising the laminate of claim
 42. 50. Swim wear comprising thelaminate of claim
 42. 51. Absorbent underpants comprising the laminateof claim
 42. 52. An adult incontinence product comprising the laminateof claim
 42. 53. A feminine hygiene product comprising the laminate ofclaim
 42. 54. A medical product comprising the laminate of claim 42.